The handling of waste materials in hospitals, medical clinics, biological research facilities and the like requires special precautions. Various disposal items such as hypodermic needles, specimen containers or bandages and tissues, for example, may be contaminated with infectious viruses or bacteria. Waste materials of this kind should be stored in closed containers and should be sterilized prior to disposal.
Burning such wastes is not an entirely satisfactory procedure for disinfecting the material. The wastes frequently have a high moisture content and materials are often present that are not readily combustible. Consequently, incinerators for the purpose require a high fuel input and are costly to operate. Such incinerators must also be equipped with complex and costly equipment for preventing the discharge of pollutants into the atmosphere.
Sterilization of the contaminated waste by exposure to steam is simpler, more economical and less subject to complications arising from the need to suppress release of pollutants. Prior U.S. Pat. No. 4,374,491, issued Feb. 22, 1983, and entitled "Apparatus for Treating and Disposing of Bio-hazardous Waste and Solid Waste" discloses an advantageous waste processor for this purpose. The apparatus of that prior patent includes a housing having separate compartments for storing infectious and non-hazardous wastes. Contents of the infectious waste compartment are periodically sterilized by steam after which the compartment is opened and the sterilized waste is discharged into the non-hazardous waste compartment by a translatable ram. The wastes are periodically compacted and transferred to a transportable waste received by another translatable ram.
The apparatus is advantageous in that it consolidates the storage and disposal operations for both types of wastes while confining the steam heating to just that portion of the wastes that need, such treatment.
The sterilization operation can be prolonged by the presence of air in the infectious waste compartment and particularly by air trapped in the plastic bags or other containers in which the waste is usually disposed. Such air is an efficient thermal insulator and is not easily displaced by incoming steam. In some prior systems of the above described kind, the time required for sterilization of infectious waste is reduced by evacuating air from the infectious waste compartment prior to the introduction of steam.
The configuration of prior equipment of the above discussed kind requires that there be two openings in the structure which defines the infectious waste compartment. One such opening faces a side wall of the apparatus to enable wastes to be inserted into the infectious waste compartment. The other opening faces in a different direction to enable transfer of sterilized wastes from that compartment to the non-hazardous waste compartment.
Both openings require doors or other closures which preferably provide a hermetic seal to prevent the escape of steam during the sterilizing operation and to facilitate the evacuation of air from the compartment. The providing of two sealing doors or the like substantially complicates the construction of the apparatus, increases maintenance requirements and adds significantly to the cost of the apparatus.
The present invention is directed to overcoming one or more of the problems discussed above.